Industrial experience in the implementation of clinker-free binders of alkaline activation

Objective. Issues related to the search for new, less energy- and material- intensive binders have long been on the agenda of many world environmental forums, since the carbonate technology of Portland cement entails pollution of the surrounding atmosphere and habitat, and the price of this product is unjustifiably growing. In our opinion, alkaline cements could contribute to the construction industry. Within the framework of this work, research results have been obtained that confirm the effectiveness of the development of a clinker-free technology for producing alkaline-mixed binders and composites based on them using aluminosilicate additives, both natural and technogenic origin.Method. The methods of electron microscopy and differential thermal analysis make it possible to study the nature of the components and the processes of formation of the structure of the cement stone. Waste from the cement industry has the appropriate granulometric and chemical composition, the aluminosilicate mineralogy of the studied powders confirms their compliance with the ready-made raw mix of Portland cement clinker, which is the key to the possibility of their effective use.Result. The carried out differential thermal analyzes confirmed the presence of the following phases in the composition of cement stone on binding bonds "cement dust - alkaline activator" of zeolite, calcite, mica type muscovite, montrillonite, magnesium oxide, calcium sulfoaluminates, ettringite structure, calcium hydrochloraluminate, calcium hydrosilicate, calcium hydrosilicate calcium.Conclusion. The obtained regularities of the processes of formation of the structure of the cement binder "waste of the cement industry - Na2SiO3", will transform these developments to create strong and durable artificial building composites competing with concretes on Portland cement.

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Utilization of Iron Ore Tailings as Raw Material for Portland Cement Clinker Production

Advances in Materials Science and Engineering ◽

10.1155/2016/1596047 ◽

2016 ◽

Vol 2016 ◽

pp. 1-6 ◽

Cited By ~ 8

Author(s):

Li Luo ◽

Yimin Zhang ◽

Shenxu Bao ◽

Tiejun Chen

Keyword(s):

Portland Cement ◽

Iron Ore ◽

Mechanical Performance ◽

Mineralogical Composition ◽

Cement Industry ◽

Raw Material ◽

Cement Clinker ◽

Iron Ore Tailings ◽

Portland Cement Clinker ◽

Clinker Production

The cement industry has for some time been seeking alternative raw material for the Portland cement clinker production. The aim of this research was to investigate the possibility of utilizing iron ore tailings (IOT) to replace clay as alumina-silicate raw material for the production of Portland cement clinker. For this purpose, two kinds of clinkers were prepared: one was prepared by IOT; the other was prepared by clay as a reference. The reactivity and burnability of raw meal, mineralogical composition and physical properties of clinker, and hydration characteristic of cement were studied by burnability analysis, differential thermal analysis, X-ray diffraction, and hydration analysis. The results showed that the raw meal containing IOT had higher reactivity and burnability than the raw meal containing clay, and the use of IOT did not affect the formation of characteristic mineralogical phases of Portland cement clinker. Furthermore, the physical and mechanical performance of two cement clinkers were similar. In addition, the use of IOT was found to improve the grindability of clinker and lower the hydration heat of Portland cement. These findings suggest that IOT can replace the clay as alumina-silicate raw material for the preparation of Portland cement clinker.

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Improving the Efficiency of Slag Portland Cement by Reducing Shrinkage Deformations

Materials Science Forum ◽

10.4028/www.scientific.net/msf.992.104 ◽

2020 ◽

Vol 992 ◽

pp. 104-110

Author(s):

Svetlana V. Samchenko ◽

D.A. Zorin

Keyword(s):

Portland Cement ◽

Compression Strength ◽

Cement Hydration ◽

Early Stage ◽

Cement Clinker ◽

Cement Stone ◽

Slag Cement ◽

Portland Cement Clinker ◽

Granulated Slag ◽

Portland Slag Cement

The influence of the artificial additive introduced at the joint grinding of granulated slag, Portland cement clinker and gypsum on the Portland slag cement hydration, its compression strength at an early stage and shrinkage deformation is investigated. It was found that in the presence of sulfoferrite clinker there is an amorphization of cement stone structure with formation of stone with high density and strength in early setting. The open porosity of the hardened paste is reduced by 13 – 15 % in comparison with plain Portland slag cement. The samples strength increases by 1.55 - 1.78 times at grade stage, by 15.5 - 19.4 % in bending and by 6.4 - 11.2 % in compression.

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METHODS OF REPEATED USE OF CEMENT DUST

Вестник ГГНТУ. Технические науки ◽

10.34708/gstou.2019.15.1.003 ◽

2019 ◽

Author(s):

М.Ш. Саламанова ◽

С.А. Алиев ◽

Р.С.-А. Муртазаева

Keyword(s):

Portland Cement ◽

Raw Materials ◽

Cement Industry ◽

Cement Clinker ◽

Liquid Sodium ◽

Portland Cement Clinker ◽

Repeated Use ◽

Electrostatic Precipitators ◽

Rotary Kilns ◽

Technogenic Raw Materials

В процессе обжига портландцементного клинкера в электрофильтрах вращающихся печей скапливается большое количество пыли, как клинкерной, так и аспирационной, поэтому рациональное использование этих продуктов, содержащих определенную долю полноценного сырьевого ресурса, является актуальной задачей индустрии цемента. В данной работе представлены результаты исследований цементной пыли, проведен энергодисперсионный и сравнительный анализ исследуемых порошков, а также приводится возможный способ утилизации цементной пыли для получения бесклинкерных цементов щелочной активации и бетонов на их основе. Разработанные рецептуры бесклинкерных вяжущих с применением отходов цементной промышленности и натриевого жидкостекольного затворителя позволят получать менее затратные, прочные и долговечные композиты, которые позволят частично заменять традиционный бетон на дорогом портландцементе. Работа выполнена в рамках исследований по реализации научного проекта 1848200001 Высококачественные бетоны с повышенными эксплуатационными свойствами на основе местного природного и техногенного сырья , получившего поддержку Российского фонда фундаментальных исследований (РФФИ). In the process of firing Portland cement clinker in electrostatic precipitators, in rotary kilns, a large amount of harmful substances, both clinker and aspiration, accumulates, therefore rational use of these products leads to certain shares of a fullfledged river resource, which are derived from industrial cement. It should be noted that the reuse of dust electrostatic precipitators is impossible. The basis for obtaining durable and more resourceefficient composites is based on modern technological methods that contribute to the improvement of technical and physicomechanical properties, with the integrated application of technogenic raw materials and liquid sodium binder. The developed clinkerfree binder formulations using the cement industry wastes and sodiumbased sludge glass will make it possible to produce less expensive, durable, and durable composites that will partially replace traditional concrete with expensive portland cement.

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FEATURES OF THE STRUCTURE FORMATION OF MULTICOMPONENT BINDING SYSTEMS OF ALKALINE ACTIVATION

Вестник ГГНТУ. Технические науки ◽

10.34708/gstou.2020.91.90.007 ◽

2020 ◽

pp. 51-58

Author(s):

С-А. Ю. Муртазаев ◽

М. Ш. Саламанова ◽

Д. К-С. Батаев

Keyword(s):

Portland Cement ◽

Construction Industry ◽

Practical Importance ◽

Cement Stone ◽

Reinforced Concrete Structures ◽

Alkaline Activation ◽

Fine Powders ◽

Natural Aluminosilicate ◽

Alkaline Activator ◽

Theoretical Foundations

Разработка рецептур бесклинкерных вяжущих связок щелочной активации на основе тонкодисперсных порошков природного алюмосиликатного происхождения позволит получать новые эффективные строительные композиты. В работе раскрываются вопросы, связанные с теоретическими основами формирования структуры и прочности цементного камня на основе щелочного активатора. Результаты исследований, на наш взгляд, безусловно представляют практическую значимость для строительной отрасли, так как предлагаемые рецептуры бесклинкерных цементов способны заменить дорогой и энергоемкий портландцемент, позволяя создавать прочные и долговечные бетонные и железобетонные конструкции. The development of formulations of clinker-free binders of alkaline activation based on fine powders of natural aluminosilicate origin will make it possible to obtain new effective building composites. The paper reveals issues related to the theoretical foundations of the formation of the structure and strength of cement stone based on an alkaline activator. The research results, in our opinion, undoubtedly are of practical importance for the construction industry, since the proposed recipes for clinker-free cements can replace expensive and energy-intensive Portland cement, allowing you to create strong and durable concrete and reinforced concrete structures.

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Investigation of fly ash properties with purpose of its utilization as a secondary raw material for portland cement clinker production

Hemijska industrija ◽

10.2298/hemind0610245b ◽

2006 ◽

Vol 60 (9-10) ◽

pp. 245-252 ◽

Cited By ~ 2

Author(s):

Zvezdana Bascarevic ◽

Miroslav Komljenovic ◽

Ljiljana Petrasinovic-Stojkanovic ◽

Natasa Jovanovic ◽

Aleksandra Rosic ◽

...

Keyword(s):

Fly Ash ◽

Portland Cement ◽

Power Plants ◽

Building Materials ◽

Thermal Power ◽

Cement Industry ◽

Raw Material ◽

Cement Clinker ◽

Physical Chemical ◽

Portland Cement Clinker

In this paper the results of the investigated properties of fly ash from four thermal power plants in Serbia are presented. The physical, chemical, mineralogical and thermal characterization of fly ash was carried out, in order to determine the possibility to utilize this material in the building materials industry, foremost in the cement industry. It was determined that, although there are differences concerning the physical, chemical, and mineralogical characteristics of the investigated samples, they are very similar concerning their thermal characteristics. It was concluded that using fly ash as one of the raw components in the mixture for Portland cement clinker synthesis, not only enables the substitution of natural resources, but it might have a positive effect on the lowering of the sintering temperature.

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